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The Mean Value Theorem |
2001-07-23 |
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Corrie pose la question :
I need to find if the mean value theorem exists. and if so, find all values c guaranteed by the theorem. f(x) = |x2-25| on the interval [-10,0]
Harley Weston lui répond. |
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What did the girls score on average? |
2001-07-20 |
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Rajesh pose la question :
The students of two schools were sitting the same test. The students attending the first school scored 74 on average; within this the average scores of the boys and the girls were 71 and 76, respectively. The corresponding scores in the other school were 84, 81 and 90, respectively. If the average score of all boys was 79, what did the girls score on average?
Penny Nom lui répond. |
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Matrix reconstruction |
2001-07-19 |
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Guy pose la question :
Is there a way to get the sums of rows, columns and diagonals of an n x n matrix to reconstruct the original matrix?
Walter Whiteley and Patrick Maidorn lui répond. |
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Hours worked |
2001-07-18 |
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Carlos pose la question :
I have a simple question:whats the formula to transform time into decimals? more exactly im working on a spreadsheet and i want to be able to type in for example hours worked: 11- 11:30 pm and a formula would tell me 12.5 hours how do i do it?
Patrick Maidorn lui répond. |
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Generating uniquie 2 digit numbers |
2001-07-16 |
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Anthony pose la question :
What methodology can I use to generate uniquie 2 digit numbers from unique 7 digit numbers. Of'course the total number of 7-digit numbers is not greater than 99.
Penny Nom lui répond. |
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Rhombus |
2001-07-16 |
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William pose la question :
Calculate the internal angles of a rhombus given measurments of all four sides only.
Walter Whiteley lui répond. |
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Margin of error |
2001-07-13 |
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Jim pose la question :
If a survey was completed by four different groups of people as indicated below what would the over-all margin of error be for this survey given the fact that the number of people in each group were different?
Group # polled Margin of error
A. 779 +/- 4%
B. 315 +/- 7%
C. 323 +/- 6%
D. 254 +/- 9%
Andrei Volodin lui répond. |
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6,000,000,000,000,000,000 |
2001-07-12 |
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James pose la question :
How would I express 6,000,000,000,000,000,000 in words?
Leeanne Boehm lui répond. |
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The speed of the boat |
2001-07-12 |
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Sharon pose la question :
A motor boat is travelling in a southeasterly direction in water that is flowing from the south at 2km per hour. Show that the speed of the boat is (6 times the square root of 2) km per hour, given that it can travel at 10km per hour in still water.
Penny Nom lui répond. |
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Comparing means and standard deviations |
2001-07-11 |
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Shelly pose la question :
Is there a way to compare means and standard deviations that come from different size samples? Is there an equation that can normalize sample size?
Andrei Volodin lui répond. |
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Investing $5,000 |
2001-07-09 |
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A student pose la question :
A principal amount of $5,000 was invested in a savings account for 5 years.The interest earned was $500.Use the simple interest formula to find the annual rate of interest.
Penny Nom lui répond. |
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Cakes and ribbons |
2001-07-05 |
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Jennifer pose la question :
- A cake recipe calls for 3 1/4 cups of flour. You already put in 1 3/4 cups. How much more should you add?
- You have 3/4 yard of ribbon. How many 1/8-yard pieces can you cut the ribbon into?
Penny Nom lui répond. |
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Some irrational numbers |
2001-07-03 |
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Kellie pose la question :
- Is it possible to write pi as a fraction?
- Is it possible to write the square root of 2 as a fraction.. Explain why?
Harley Weston lui répond. |
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Arclength of an ellipse |
2001-07-03 |
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A hobbyist pose la question :
What is the equation (with the length of the arc as a variable) for one quadrant of the ellipse,...
Claude tardif lui répond. |
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A confidence interval |
2001-06-28 |
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Murray pose la question :
An investigator wants to find out of there are any difference in "skills" between full and part time students. Records show the following:
Student Mean Score Std Dev Number
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Full time 83 12 45
Part time 70 15 55
Compute a 95% confidence interval for the difference in mean scores.
Andrei Volodin lui répond. |
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